Dataset Information

Using pressure-driven flow systems to evaluate laser speckle contrast imaging.

ABSTRACT:

Significance

Microfluidic flow phantom studies are commonly used for characterizing the performance of laser speckle contrast imaging (LSCI) instruments. The selection of the flow control system is critical for the reliable generation of flow during testing. The majority of recent LSCI studies using microfluidics used syringe pumps for flow control.

Aim

We quantified the uncertainty in flow generation for a syringe pump and a pressure-regulated flow system. We then assessed the performance of both LSCI and multi-exposure speckle imaging (MESI) using the pressure-regulated flow system across a range of flow speeds.

Approach

The syringe pump and pressure-regulated flow systems were evaluated during stepped flow profile experiments in a microfluidic device using an inline flow sensor. The uncertainty associated with each flow system was calculated and used to determine the reliability for instrument testing. The pressure-regulated flow system was then used to characterize the relative performance of LSCI and MESI during stepped flow profile experiments while using the inline flow sensor as reference.

Results

The pressure-regulated flow system produced much more stable and reproducible flow outputs compared to the syringe pump. The expanded uncertainty for the syringe pump was 8 to 20× higher than that of the pressure-regulated flow system across the tested flow speeds. Using the pressure-regulated flow system, MESI outperformed single-exposure LSCI at all flow speeds and closely mirrored the flow sensor measurements, with average errors of 4.6%±2.6% and 15.7%±4.6% , respectively.

Conclusions

Pressure-regulated flow systems should be used instead of syringe pumps when assessing the performance of flow measurement techniques with microfluidic studies. MESI offers more accurate relative flow measurements than traditional LSCI across a wide range of flow speeds.

SUBMITTER: Sullender CT

PROVIDER: S-EPMC10007838 | biostudies-literature | 2023 Mar

REPOSITORIES: biostudies-literature

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Publications

Using pressure-driven flow systems to evaluate laser speckle contrast imaging.

Sullender Colin T CT Santorelli Adam A Richards Lisa M LM Mannava Pawan K PK Smith Christopher C Dunn Andrew K AK

Journal of biomedical optics 20230311 3

<h4>Significance</h4>Microfluidic flow phantom studies are commonly used for characterizing the performance of laser speckle contrast imaging (LSCI) instruments. The selection of the flow control system is critical for the reliable generation of flow during testing. The majority of recent LSCI studies using microfluidics used syringe pumps for flow control.<h4>Aim</h4>We quantified the uncertainty in flow generation for a syringe pump and a pressure-regulated flow system. We then assessed the pe ...[more]

PMID: 36915371

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Dataset Information

Using pressure-driven flow systems to evaluate laser speckle contrast imaging.

Significance

Aim

Approach

Results

Conclusions

Publications

Using pressure-driven flow systems to evaluate laser speckle contrast imaging.

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